In article
<edbdacfe6ead86da540e899903fe67c9@localhost.talkaboutmac.com>,
> Is there any Carbon API available to get CPU serial number in Macosx?
PowerPC CPUs don't have a serial number. If you want a semi-unique,
semi-persistent machine identifier, you may be able to poke around in
the registry to find something you can use. Look at the documentation
for IOMasterPort() and IOServiceMatching().
So far as I know, these calls are Mach-O onlym, and there is no
PowerPlant support for them.

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David Phillip Oster